Shared Interactive Planning

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Mobile robots are an important subject of research and investments because of their capability to perform efficiently and safely a large variety of tasks, even in dangerous environments. Possible applications of mobile robots include exploration, surveillance, monitoring, search-and-rescue, good transportation, mobile-networking, etc.. In all these scenarios, the task needs to be translated by an algorithm into a trajectory to be tracked by the robot. There are several complex issues to be considered in this planning phase:

Concept

a middle-level planner updates in real-time the initial plan and provides the desired trajectory;

a low-level reactive layer corrects the desired trajectory to meet the following specifications:

ensuring feasibility of the motion given the robot constraints

the tracked trajectory remains close to the desired one

ensure obstacle avoidance

pass close to the points-of-interest near the reference trajectory

Our approach exploits the subdivision of trajectories in geometric path and timing law to simplify the planning layers. A set of geometric attributes is used to define the system state variables that control the shape of the path, thus providing an intuitive way for a human operator to interact with the planner. A decoupling mechanism is introduced to cancel the instantaneous effect of path variations on the motion references for the robot. Therefore, the instantaneous motion commands are affected only by the timing-law.

Validation and Additional Features

We have validated the framework with extensive human-in-the-loop simulations. We have also implemented several additional features